U.S. patent application number 16/084275 was filed with the patent office on 2019-03-14 for vehicle communication control device.
The applicant listed for this patent is DENSO CORPORATION. Invention is credited to Haruhiko SOGABE.
Application Number | 20190079161 16/084275 |
Document ID | / |
Family ID | 59850680 |
Filed Date | 2019-03-14 |
United States Patent
Application |
20190079161 |
Kind Code |
A1 |
SOGABE; Haruhiko |
March 14, 2019 |
VEHICLE COMMUNICATION CONTROL DEVICE
Abstract
A vehicle communication control device used for a vehicle
includes a nearby vehicle information acquirer, a subject vehicle
information generator, an assistance information generator, a
difference calculator, and a cycle changer. The nearby vehicle
information acquirer successively acquires nearby vehicle
information representing running condition of a nearby vehicle and
generation time of the nearby vehicle information. The subject
vehicle information generator cyclically generates subject vehicle
information representing running condition of a subject vehicle.
The assistance information generator generates assistance
information for driving assistance of the subject vehicle by using
the nearby vehicle information and the subject vehicle information.
The difference calculator calculates a difference between
generation time of the most recent subject vehicle information and
generation time of the most recent nearby vehicle information. The
cycle changer changes a generation cycle of the subject vehicle
information so as to decrease the difference.
Inventors: |
SOGABE; Haruhiko;
(Kariya-city, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DENSO CORPORATION |
Kariya-city, Aichi-pref. |
|
JP |
|
|
Family ID: |
59850680 |
Appl. No.: |
16/084275 |
Filed: |
February 22, 2017 |
PCT Filed: |
February 22, 2017 |
PCT NO: |
PCT/JP2017/006451 |
371 Date: |
September 12, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G08G 1/163 20130101;
G01S 5/14 20130101; G01S 5/0226 20130101; G01S 5/0242 20130101;
G08G 1/09 20130101; G01S 5/0236 20130101; G01S 5/0284 20130101 |
International
Class: |
G01S 5/14 20060101
G01S005/14; G01S 5/02 20060101 G01S005/02 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 18, 2016 |
JP |
2016-055973 |
Claims
1. A vehicle communication control device used for a vehicle,
comprising: a nearby vehicle information acquirer configured to
successively acquire nearby vehicle information representing a
running condition of at least one nearby vehicle around a subject
vehicle and generation time of the nearby vehicle information,
wherein the nearby vehicle information and the generation time are
generated in an in-vehicle unit mounted on the at least one nearby
vehicle and successively transmitted by communication from outside
the subject vehicle; a subject vehicle information generator
configured to cyclically generate subject vehicle information
representing a running condition of the subject vehicle; an
assistance information generator configured to generate assistance
information for driving assistance of the subject vehicle by using
the nearby vehicle information and the subject vehicle information;
a difference calculator configured to calculate a difference
between generation time of the most recent subject vehicle
information and generation time of the most recent nearby vehicle
information; and a cycle changer configured to change a generation
cycle of the subject vehicle information in the subject vehicle
information generator so as to decrease the difference.
2. The vehicle communication control device according to claim 1,
wherein the assistance information generator uses the most recent
nearby vehicle information and the most recent subject vehicle
information to generate the assistance information for the driving
assistance that assists driving of a driver by controlling travel
of the subject vehicle.
3. The vehicle communication control device according to claim 1,
wherein the at least one nearby vehicle includes a plurality of
nearby vehicles, wherein the vehicle communication control device
further comprises a target determiner configured to determine a
nearby vehicle to be prioritized from the plurality of nearby
vehicles by using the nearby vehicle information and the subject
vehicle information when the nearby vehicle information acquirer
acquires the nearby vehicle information of the plurality of nearby
vehicles, and wherein the difference calculator is configured to
calculate a difference between the generation time of the most
recent nearby vehicle information concerning the nearby vehicle
determined to be prioritized and the generation time of the most
recent subject vehicle information.
4. The vehicle communication control device according to claim 1,
wherein the nearby vehicle information acquirer is configured to
acquire the nearby vehicle information including a position of the
nearby vehicle, wherein the subject vehicle information generator
is configured to generate the subject vehicle information including
a position of the subject vehicle, wherein the vehicle
communication control device further comprises: a map acquirer
configured to acquire map data; a priority determiner configured to
determine either the nearby vehicle or the subject vehicle to be
prioritized by using the position of the nearby vehicle, the
position of the subject vehicle, and the map data; and a change
requester configured to transmit request information to the nearby
vehicle, the request information requesting a change in a
generation cycle of the nearby vehicle information in the nearby
vehicle so as to decrease the difference, wherein the request
information includes the difference, wherein, when the priority
determiner determines that the nearby vehicle is to be prioritized,
the cycle changer changes the generation cycle of the subject
vehicle information in the subject vehicle information generator so
as to decrease the difference, and wherein, when the priority
determiner determines that the subject vehicle is to be
prioritized, the change requester transmits the request information
to the nearby vehicle.
5. The vehicle communication control device according to claim 4,
wherein, by using the position of the nearby vehicle, the position
of the subject vehicle, and the map data, the priority determiner
is configured to: determine that the subject vehicle is to be
prioritized when the nearby vehicle travels on a non-priority road
and the subject vehicle travels on a priority road; and determine
that the nearby vehicle is to be prioritized when the nearby
vehicle travels on the priority road and the subject vehicle
travels the non-priority road.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is based on Japanese Patent Application No.
2016-55973 filed on Mar. 18, 2016, the disclosure of which is
incorporated herein by reference.
TECHNICAL FIELD
[0002] The present disclosure relates to a vehicle communication
control device that acquires, via communication, information of a
nearby vehicle used for driving assistance of a subject
vehicle.
BACKGROUND ART
[0003] Patent Literature 1 discloses the technology that performs
driving assistance of a subject vehicle by using vehicle
information of a different vehicle acquired via communication from
the different vehicle and vehicle information of the subject
vehicle acquired in the subject vehicle. The technology disclosed
in Patent Literature 1 calculates a time delay until the nearby
vehicle affects the subject vehicle based on a position of the
nearby vehicle and a position of the subject vehicle. The position
of the nearby vehicle is generated from a navigation system of the
nearby vehicle and is acquired from the nearby vehicle through
inter-vehicle communication. The position of the subject vehicle is
acquired from a GPS of the subject vehicle. A nearby vehicle
targeted at driving assistance is prioritized for determination
based on the calculated time delay. The driving assistance is
performed to preferentially notify a driver of information about a
highly prioritized nearby vehicle.
PRIOR ART LITERATURE
Patent Literature
[0004] Patent literature 1: JP 2010-108344 A
SUMMARY OF INVENTION
[0005] Generally, however, there is no synchronization between a
cycle to acquire the position of the nearby vehicle in the
navigation system of the nearby vehicle and a cycle to acquire the
position of the subject vehicle by using the GPS of the subject
vehicle. According to the technology disclosed in Patent Literature
1, the positional relation between the subject vehicle and the
nearby vehicle differs from the actual positional relation by at
least a difference between the cycle to acquire the position of the
nearby vehicle and the cycle to acquire the position of the subject
vehicle. A calculated time delay differs from the actual one. As a
result, the varied time delay causes the timing of the driving
assistance based on the time delay to differ from the timing a user
feels proper. A driver may feel unsatisfied with the driving
assistance.
[0006] It is an object of the present disclosure to provide a
vehicle communication control device capable of minimizing
dissatisfaction of a driver with driving assistance using vehicle
information of a nearby vehicle acquired by communication from
outside a subject vehicle and vehicle information of the subject
vehicle acquired in the subject vehicle.
[0007] According to an aspect of the present disclosure, a vehicle
communication control device is used for a vehicle and includes a
nearby vehicle information acquirer, a subject vehicle information
generator, an assistance information generator, a difference
calculator, and a cycle changer. The nearby vehicle information
acquirer is configured to successively acquire nearby vehicle
information representing a running condition of at least one nearby
vehicle around a subject vehicle and generation time of the nearby
vehicle information. The nearby vehicle information and the
generation time are generated in an in-vehicle unit mounted on the
at least one nearby vehicle and successively transmitted by
communication from outside the subject vehicle. The subject vehicle
information generator is configured to cyclically generate subject
vehicle information representing a running condition of the subject
vehicle. The assistance information generator is configured to
generate assistance information for driving assistance of the
subject vehicle by using the nearby vehicle information and the
subject vehicle information. The difference calculator is
configured to calculate a difference between generation time of the
most recent subject vehicle information and generation time of the
most recent nearby vehicle information. The cycle changer is
configured to change a generation cycle of the subject vehicle
information in the subject vehicle information generator so as to
decrease the difference.
[0008] According to the aspect of the present disclosure, the
generation cycle of the subject vehicle information is changed so
as to reduce the difference between the generation time of the most
recent nearby vehicle information concerning the targeted nearby
vehicle and the generation time of the most recent subject vehicle
information. As such, the difference is decreased.
[0009] When the difference between the generation time of the
nearby vehicle information and the generation time of the subject
vehicle information is decreased, the assistance information
generated in the assistance information generator by using these
pieces of information therefore more accurately reflects the actual
running condition relation between the subject vehicle and the
nearby vehicle. The driving assistance using the assistance
information can therefore more accurately reflect the actual
running condition relation between the subject vehicle and the
nearby vehicle. As a result, it is possible to minimize
dissatisfaction of a driver with the driving assistance using
vehicle information of the nearby vehicle acquired by communication
from outside the subject vehicle and vehicle information of the
subject vehicle acquired in the subject vehicle.
BRIEF DESCRIPTION OF DRAWINGS
[0010] The above and other objects, features and advantages of the
present disclosure will become more apparent from the following
detailed description made with reference to the accompanying
drawings, in which:
[0011] FIG. 1 is a diagram illustrating an example of a schematic
configuration of a driving assistance system 3;
[0012] FIG. 2 is a diagram illustrating an example of a schematic
configuration of a vehicle-side unit 1;
[0013] FIG. 3 is a diagram illustrating an example of a schematic
configuration of a communication data processor 10;
[0014] FIG. 4 is a flowchart illustrating an example of a flow of a
generation cycle changing and related process on the communication
data processor 10;
[0015] FIG. 5 is a diagram illustrating an example of a schematic
configuration of a communication data processor 10a; and
[0016] FIG. 6 is a flowchart illustrating an example of a flow of a
generation cycle changing and related process on the communication
data processor 10a.
DESCRIPTION OF EMBODIMENTS
[0017] Embodiments and modifications for the disclosure will be
described with reference to the accompanying drawings. The same
reference numerals may be given to parts having the same functions
illustrated in the drawings used to describe the embodiments and
the modifications hitherto and the related description may be
omitted for convenience sake. The parts given the same reference
numerals can be made clear by reference to the description in the
other embodiments and/or modifications.
[0018] Embodiments and modifications described below are applicable
to regions legislating driving on the left-hand side of the road.
Regions legislating driving on the right-hand side of the road
requires reversing the descriptions about the right and the left in
the embodiments below.
First Embodiment
[0019] <Schematic Configuration of Driving assistance System
3>
[0020] The description below explains a first embodiment of the
present invention with reference to the accompanying drawings. As
illustrated in FIG. 1, a driving assistance system 3 includes a
vehicle-side unit 1 and a center 2. The vehicle-side unit 1 is
mounted on each of a plurality of vehicles.
[0021] The vehicle-side unit 1 communicates with the vehicle-side
unit 1 mounted on a nearby vehicle around a subject vehicle and
communicates with the center 2. The center 2 is available as a
server, for example. The center 2 acquires vehicle information
transmitted from the vehicle-side unit 1 of a certain vehicle via a
public telecommunication network and transfers the vehicle
information to the vehicle-side unit 1 of another vehicle. The
driving assistance system 3 allows the vehicle-side units 1 to
directly communicate with each other or to indirectly communicate
with each other via the center 2.
[0022] Direct communication between the vehicle-side units 1
(hereinafter referred to as inter-vehicle communication) may use a
radio wave of 760 MHz band and may comply with the communication
standard of WAVE (Wireless Access in Vehicular Environment). The
inter-vehicle communication may use other frequency bands such as
2.4 GHz and 5.9 GHz for radio waves. The inter-vehicle
communication may use communication standards other than WAVE.
[0023] Communication between the vehicle-side units 1 via the
center 2 (hereinafter referred to as communication via the center)
may use public telecommunication networks such as a mobile
telephone network and the Internet. The center 2 manages a vehicle
position of each vehicle by successively updating and storing the
vehicle position contained in the vehicle information successively
transmitted from the vehicle-side unit 1 of each vehicle. Suppose
the center 2 acquires the vehicle information transmitted from the
vehicle-side unit 1 of a certain vehicle. In this case, the
communication via the center specifies nearby vehicles located
around the vehicle based on the vehicle position contained in the
vehicle information and the managed vehicle position of each
vehicle and transfers the acquired vehicle information to the
nearby vehicles. The center 2 may include one or more servers.
[0024] <Schematic Configuration of Vehicle-Side Unit 1>
[0025] The description below explains a schematic configuration of
the vehicle-side unit 1 with reference to FIG. 2. As illustrated in
FIG. 2, the vehicle-side unit 1 includes a communication data
processor 10, a locator 20, an inter-vehicle communication
instrument 30, a DCM (Data Communication Module) 40, a HCU (Human
Machine Interface Control Unit) 50, a vehicle controller ECU 60,
and a driving assistance ECU 70. For example, the communication
data processor 10, the locator 20, the inter-vehicle communication
instrument 30, the HCU 50, the vehicle controller ECU 60, and the
driving assistance ECU 70 are connected to an in-vehicle LAN and
can exchange information with each other through the communication.
The foregoing is only an example. The DCM 40 may be connected to
the in-vehicle LAN. The inter-vehicle communication instrument 30
may not be connected to the in-vehicle LAN but may be connected to
the communication data processor 10.
[0026] A locator 20 includes a GNSS (Global Navigation Satellite
System) receiver, an inertia sensor such as a 3D gyro sensor, and a
map database (hereinafter denoted as DB) to store map data. The
GNSS receiver receives positioning signals from a plurality of
artificial satellites. The 3D gyro sensor includes a 3-axis gyro
sensor and a 3-axis acceleration sensor, for example. The locator
20 measures vehicle positions of the subject vehicle by combining a
positioning signal received by the GNSS receiver and a measuring
result from the inertia sensor. The vehicle position can be
represented as latitude/longitude coordinates, for example.
[0027] The locator 20 reads map data from the map DB. The map data
provides road information such as link data and node data around
the subject vehicle. The locator 20 outputs the vehicle position of
the subject vehicle and the read map data around the subject
vehicle to an in-vehicle LAN. The link data includes a unique
number specifying a link (link ID), a link length indicating the
length of a link, a link direction, shape information about a link,
node coordinates (latitude/longitude) corresponding to the
beginning and the end of a link, and a road attributed. The road
attribute includes a road name, a road type, a road width, the
number of lanes, and a speed limit value. The node data includes a
node ID assigned a unique number corresponding to each node on the
map, node coordinates, a node name, a node type, a connection link
ID denoting the link ID of a link connected to the node, and an
intersection type.
[0028] The locator 20 may be optional when the vehicle-side unit 1
includes an apparatus to detect vehicle positions of the subject
vehicle and memory to store the map data. An onboard navigation
system may be used, for example.
[0029] The inter-vehicle communication instrument 30 is provided as
a communication module that performs the inter-vehicle
communication with the inter-vehicle communication instrument 30 of
the vehicle-side unit 1 mounted on a nearby vehicle around the
subject vehicle. The inter-vehicle communication instrument 30
includes a narrowband communication antenna and a narrowband
transceiver. The narrowband communication antenna transmits and
receives radio waves of frequency bands used for the inter-vehicle
communication. The narrowband transceiver demodulates a signal
received at the narrowband communication antenna and outputs the
signal to the communication data processor 10. The narrowband
transceiver modulates data input from the communication data
processor 10 and outputs the data to the narrowband communication
antenna. The data output to the narrowband communication antenna is
transmitted from the narrowband communication antenna.
[0030] The DCM 40 is provided as a communication module used for
telematics. The DCM 40 includes a wide area communication antenna
and a wide area transceiver. The wide area communication antenna
transmits and receives radio waves of frequency bands used for
wireless communication with a base station of the public
telecommunication network. The wide area transceiver demodulates a
signal received at the wide area communication antenna and outputs
the signal to the communication data processor 10. The wide area
transceiver modulates data input from the communication data
processor 10 and outputs the data to the wide area communication
antenna. The data output to the wide area communication antenna is
transmitted from the wide area communication antenna. The
communication module used for telematics has been described as an
example of the communication module used for the communication via
the center. However, the communication module is not limited to the
one used for telematics if the communication module can communicate
with the center 2 via the public telecommunication network.
[0031] An HCU 50 includes a CPU, volatile memory, nonvolatile
memory, I/O, and a bus connecting these components. The HCU 50
performs various processes by executing a control program stored in
the nonvolatile memory. For example, information is provided from a
display apparatus 51 and an audio output apparatus 52. The display
apparatus 51 includes a combination meter, CID (Center Information
Display), and HUD (Head-Up Display), for example. Information is
provided by displaying text and/or images. The audio output
apparatus 52 includes an audio speaker, for example, to provide
information audibly.
[0032] The vehicle controller ECU 60 is available as an electronic
control device that performs acceleration and deceleration control
and/or steering control over the subject vehicle. The vehicle
controller ECU 60 includes a steering ECU to perform the steering
control, and a power unit control ECU and a brake ECU to perform
the acceleration and deceleration. The vehicle controller ECU 60
acquires detection signals output from sensors such as an
accelerator position sensor, a brake pedal force sensor, a steering
angle sensor, and a vehicle speed sensor mounted on the subject
vehicle. The vehicle controller ECU 60 outputs control signals to
travel control devices such as an electronically controlled
throttle, a brake actuator, and an EPS (Electric Power Steering)
motor. The vehicle controller ECU 60 can output detection signals
from the above-mentioned sensors to the in-vehicle LAN.
[0033] The driving assistance ECU 70 is configured as a computer
including a CPU, volatile memory, nonvolatile memory, I/O, and a
bus connecting these components. The driving assistance ECU 70
performs various processes by executing a control program stored in
the nonvolatile memory. For example, the driving assistance ECU 70
performs a driving assistance that assists driving of the subject
vehicle based on the vehicle information about the nearby vehicle
around the subject vehicle acquired from the communication data
processor 10, and the vehicle position and the map data for the
subject vehicle acquired from the locator 20.
[0034] Driving assistance examples include collision avoidance
assistance and right turn assistance. The collision avoidance
assistance prevents the subject vehicle from colliding with a
leading vehicle. The right turn assistance prevents the subject
vehicle from colliding with a straight oncoming vehicle when the
subject vehicle turns to the right. For example, the collision
avoidance assistance may be performed when a driving assistance ECU
70 determines that the subject vehicle goes straight based on a
signal from a turn signal lever of the subject vehicle. The right
turn assistance may be performed when the driving assistance ECU 70
determines that the subject vehicle turns to the right based on a
signal from the turn signal lever of the subject vehicle. One or
more ICs as hardware may provide all or part of functions performed
by the driving assistance ECU 70.
[0035] A communication data processor 10 is configured as a
computer including volatile memory, nonvolatile memory, I/O, and a
bus connecting these components. The communication data processor
10 performs various processes by executing a control program stored
in the nonvolatile memory. For example, the communication data
processor 10 generates and transmits vehicle information containing
a state quantity concerning subject vehicle traveling. Information
used for the driving assistance is generated by using vehicle
information about the subject vehicle generated in the subject
vehicle and vehicle information about a nearby vehicle acquired
from the nearby vehicle through the use of communication. Moreover,
a cycle to generate vehicle information about the subject vehicle
is changed to decrease a difference in the time to generate vehicle
information about the subject vehicle and vehicle information about
the nearby vehicle. One or more ICs as hardware may provide all or
part of functions performed by the communication data processor 10.
The communication data processor 10 will be described in detail
below.
[0036] <Schematic Configuration of Communication Data Processor
10>
[0037] The description below explains a schematic configuration of
the communication data processor 10 with reference to FIG. 3. As
illustrated in FIG. 3, the communication data processor 10 includes
function blocks such as a sensor information acquirer 101, a
temporary storage 102, a data generator 103, a narrowband
communication processor 104, a wide area communication processor
105, a manager 106, a data processor 107, and a cycle changer 108.
The communication data processor 10 is comparable to a vehicle
communication control device.
[0038] The sensor information acquirer 101 acquires sensor
information, namely, various information that is output from the
locator 20 and a vehicle controller ECU 60 via a vehicle LAN and
represents state quantities concerning subject vehicle traveling.
Various sensors detect the state quantities. The sensor information
includes a vehicle position, a speed, and an orientation (namely, a
traveling direction) of the subject vehicle, for example. The
sensor information acquirer 101 may acquire the sensor information
from various sensors without using the ECU. The temporary storage
102 stores the sensor information acquired by the sensor
information acquirer 101 for a predetermined time period. The
temporary storage 102 may be provided as nonvolatile memory.
[0039] The data generator 103 generates vehicle information
indicating a running condition of the subject vehicle at the time
of generating the vehicle information at a predetermined generation
cycle based on the sensor information stored in the temporary
storage 102. The generation cycle may be set to 100 msec, for
example. The vehicle information generated by the data generator
103 is stored in the temporary storage 102 for a predetermined time
period and is supplied to the narrowband communication processor
104 and the wide area communication processor 105. The data
generator 103 is comparable to a subject vehicle information
generator.
[0040] Each time the data generator 103 supplies vehicle
information, the narrowband communication processor 104 generates a
data packet containing the vehicle information and outputs the data
packet to an inter-vehicle communication instrument 30. The data
packet containing the vehicle information contains a time stamp
indicating the time to generate the vehicle information and
identification information to identify a transmission origin of the
vehicle information in addition to the vehicle information about
the subject vehicle. The description below explains an example of
using the identification information as a vehicle ID of the subject
vehicle. The inter-vehicle communication instrument 30 modulates a
data packet supplied from the narrowband communication processor
104 and broadcasts the data packet. For example, a generation cycle
to generate the vehicle information by the data generator 103 may
correspond to a transmission cycle for the narrowband communication
processor 104 to transmit data packets.
[0041] The narrowband communication processor 104 acquires a data
packet containing the vehicle information about the nearby vehicle
via the inter-vehicle communication instrument 30. That data packet
is transmitted from the narrowband communication processor 104 of
the vehicle-side unit 1 mounted on the nearby vehicle in relation
to the subject vehicle. The data packet containing the vehicle
information about the nearby vehicle contains the time stamp
indicating the time to generate the vehicle information and the
vehicle ID of this nearby vehicle in addition to the vehicle
information representing running conditions such as the vehicle
position, the speed, and the orientation of the nearby vehicle
similarly to the data packet containing the vehicle information
about the subject vehicle as above. The narrowband communication
processor 104 provides the acquired data packet to the manager
106.
[0042] The wide area communication processor 105 generates a data
packet that is common to the data packet generated in the
narrowband communication processor 104 and contains the vehicle
information generated by the data generator 103. The generated data
packet is output to a DCM 40. In this context, being common
signifies consistency in the vehicle information, the time stamp,
and the vehicle ID. The wide area communication processor 105 may
generate a data packet at a generation cycle corresponding to an
integral multiple of the cycle for the narrowband communication
processor 104 to generate a data packet, for example. The data
packet may be generated at a generation cycle equal to the cycle
for the narrowband communication processor 104 to generate a data
packet. When the data packet is input from the wide area
communication processor 105, the DCM 40 transmits the data packet
to a center 2 via a base station and a public communication
network. The data packet transmitted from the DCM 40 is transmitted
to the nearby vehicle in relation to the subject vehicle via the
base station, the public communication network, and the center
2.
[0043] The wide area communication processor 105 of the
vehicle-side unit 1 mounted on the nearby vehicle in relation to
the subject vehicle transmits the data packet containing the
vehicle information about the nearby vehicle via the center 2. The
wide area communication processor 105 acquires this data packet via
the DCM 40. The wide area communication processor 105 supplies the
acquired data packet to the manager 106.
[0044] A data packet may be acquired from one of the narrowband
communication processor 104 and the wide area communication
processor 105. In this case, the manager 106 determines whether the
acquired data packet and the data packet stored in the temporary
storage 102 maintain the same contents. In this context, the same
contents signify uniformity in terms of the time stamp, the vehicle
ID, and the vehicle information contained in the data packet.
Whether the data packet maintains the same contents can be
determined by determining whether the time stamp and the vehicle ID
equate with the corresponding ones. The time stamp and the vehicle
ID equate with the corresponding ones only when the nearby vehicle
transmits common data packets via a plurality of types of
communication paths such as the inter-vehicle communication and the
communication via the center and the vehicle-side unit 1 of the
subject vehicle also receives the common data packets.
[0045] The manager 106 may determine that the contents of the
acquired data packet differ from the contents of the data packet
stored in the temporary storage 102. In this case, the manager 106
delivers the data packet to the data processor 107 and stores the
data packet in the temporary storage 102 for a predetermined time
period. The manager 106 may determine that the contents of the
acquired data packet equal the contents of the data packet stored
in the temporary storage 102. In this case, the manager 106
discards the acquired data packet. A common data packet may be
transmitted via the types of communication paths such as the
inter-vehicle communication and the communication via the center.
In this case, the temporary storage 102 stores the data packet
output from the narrowband communication processor 104 or the wide
area communication processor 105, whichever acquires the data
packet first.
[0046] The data processor 107 includes a data acquirer 171, a
target determiner 172, a difference calculator 173, and an
assistance information generator 174. The description below
explains the data acquirer 171, the target determiner 172, the
difference calculator 173, and the assistance information generator
174 included in the data processor 107.
[0047] The data acquirer 171 acquires data packets successively
supplied from the manager 106. The data packet arrives from the
nearby vehicle based on communication outside the subject vehicle.
The data acquirer 171 is comparable to a nearby vehicle information
acquirer. The communication data processor 10 included in the
vehicle-side unit 1 mounted on the nearby vehicle is comparable to
an in-vehicle unit.
[0048] The target determiner 172 determines a nearby vehicle to be
prioritized as a prioritized target out of nearby vehicles from
which the data acquirer 171 acquires data packets. The nearby
vehicle as a prioritized target is determined by using the vehicle
information about nearby vehicle and the vehicle information about
subject vehicle. The vehicle information about nearby vehicle
concerns the nearby vehicles from which the data acquirer 171
acquires data packets within a predetermined time period such as
100 msec, for example. The vehicle information about subject
vehicle is generated in the data generator 103. The prioritized
target corresponds to a nearby vehicle most preferentially targeted
at the driving assistance.
[0049] According to the embodiment, the description below explains
a case of determining one of nearby vehicles as a prioritized
target on condition that the nearby vehicle indicates the shortest
TTC (time to collision) with the subject vehicle. The TTC is
calculated based on the vehicle position, the speed, and the
orientation contained in the vehicle information. The TTC can be
calculated by dividing a distance from the vehicle position of the
subject vehicle to an estimated crossing position with the nearby
vehicle by a relative speed at the vehicle position in relation to
the subject vehicle.
[0050] The estimated crossing position can be determined based on a
vehicular swept path of the subject vehicle estimated from the
vehicle position and the orientation of the subject vehicle and a
vehicular swept path of the nearby vehicle estimated from the
vehicle position and the orientation of the nearby vehicle. The
assistance information generator 174 may calculate the TTC. There
may be a case where the data acquirer 171 acquires data packets
from only one nearby vehicle within a predetermined time period. In
such a case, the target determiner 172 may determine this nearby
vehicle as a target.
[0051] The difference calculator 173 calculates a difference
between the generation time to generate the most recent vehicle
information about the nearby vehicle determined as a target by the
target determiner 172 and the generation time to generate the most
recent vehicle information about the subject vehicle generated by
the data generator 103. An example is to calculate a difference
found by subtracting the generation time to generate the most
recent vehicle information about the nearby vehicle from the
generation time to generate the most recent vehicle information
about the subject vehicle. The generation time to generate the most
recent vehicle information about the nearby vehicle determined as a
target can be specified from the time stamp contained in the most
recent data packet acquired by the data acquirer 171 in terms of
the nearby vehicle.
[0052] Namely, the difference calculation uses the generation time
to generate the first arriving one of the pieces of common vehicle
information transmitted via various types of communication paths.
The generation time to generate the most recent vehicle information
about the subject vehicle can be specified from the time stamp
contained in the vehicle information stored in the temporary
storage 102. The difference calculator 173 outputs the calculated
difference to the cycle changer 108.
[0053] The assistance information generator 174 generates
assistance information used for driving assistance in the subject
vehicle by using the vehicle information contained in nearby
vehicle data packets successively acquired by the data acquirer 171
and the vehicle information about the subject vehicle successively
generated by the data generator 103. An example is to calculate the
TTC between the subject vehicle and the nearby vehicle from the
most recent vehicle information about the nearby vehicle as a
target determined by the target determiner 172 and the most recent
vehicle information about the subject vehicle generated by the data
generator 103. The calculated TTC is output as the assistance
information to the driving assistance ECU 70.
[0054] The TTC is output from the assistance information generator
174 to the driving assistance ECU 70 and is used for driving
assistance in the driving assistance ECU 70. When the TTC is
smaller than or equal to a threshold value, for example, the
driving assistance ECU 70 may issue an instruction to the HCU 50
and call attention by providing information from the display
apparatus 51 and/or the audio output apparatus 52. Alternatively,
when the TTC is smaller than or equal to a threshold value, the
driving assistance ECU 70 may issue an instruction to the vehicle
controller ECU 60 to control deceleration of the subject vehicle or
control steering of the subject vehicle.
[0055] The cycle changer 108 changes a generation cycle in the data
generator 103 to generate the vehicle information about the subject
vehicle so as to decrease a difference calculated by the difference
calculator 173. For example, when the difference calculator 173
inputs a positive difference value, it just needs to shorten the
generation cycle for the vehicle information about the subject
vehicle so as to correspond to the difference. Alternatively, when
the difference calculator 173 inputs a negative difference value,
it just needs to extend the generation cycle for the vehicle
information about the subject vehicle so as to correspond to the
difference.
[0056] The description below explains a process (hereinafter
referred to as a generation cycle changing and related process)
related to changing the generation cycle of the vehicle information
in the communication data processor 10. The flowchart in FIG. 4 may
start when an ignition power supply for the subject vehicle turns
on, for example.
[0057] At step S1, when a processing cycle is available (YES at
S1), the process proceeds to step S2. When the processing cycle is
unavailable (NO at S1), the process proceeds to step S5. The
processing cycle can be set to any value such as 100 msec. At step
S2, the target determiner 172 determines the nearby vehicle as a
prioritized target based on a nearby vehicle data packet acquired
by the data acquirer 171 within the processing cycle.
[0058] At step S3, the difference calculator 173 calculates a
difference between generation time to generate the most recent
vehicle information about the nearby vehicle determined as a target
at S2 and the generation time for the data generator 103 to
generate the most recent vehicle information for the subject
vehicle. At step S4, the cycle changer 108 changes the generation
cycle in the data generator 103 to generate the vehicle information
about the subject vehicle based on the difference calculated at S3
so as to decrease the difference.
[0059] At step S5, the generation cycle changing and related
process may reach termination timing (YES at S5). In this case, the
generation cycle changing and related process terminates. The
generation cycle changing and related process may not reach the
termination timing (NO at S5). In this case, the process returns to
S1 and is repeated. The timing to terminate the generation cycle
changing and related process may correspond to turning off the
ignition power supply for the subject vehicle, for example.
[0060] According to the above-mentioned configuration of the first
embodiment, the generation cycle for the vehicle information about
the subject vehicle is shortened by the time corresponding to a
difference found by subtracting the generation time to generate the
most recent vehicle information about the nearby vehicle determined
as a prioritized target from the generation time to generate the
most recent vehicle information about the subject vehicle. It is
therefore possible to reduce a difference between the generation
time for the vehicle information acquired next from the nearby
vehicle via the communication and the generation time for the
vehicle information generated next in the subject vehicle.
[0061] The assistance information generated in the assistance
information generator 174 by using these pieces of information more
accurately reflects the actual running condition relation between
the subject vehicle and the nearby vehicle. For example, the
assistance information provided as TTC more accurately reflects the
actual positional relation and speed difference between the subject
vehicle and the nearby vehicle. The driving assistance ECU 70 using
the assistance information can therefore provide the driving
assistance more accurately reflecting the actual running condition
relation between the subject vehicle and the nearby vehicle. As a
result, it is possible to minimize dissatisfaction of a driver with
the driving assistance using vehicle information about the nearby
vehicle acquired by communication from outside the subject vehicle
and vehicle information about the subject vehicle acquired in the
subject vehicle.
[0062] According to the configuration of the first embodiment, the
most highly prioritized nearby vehicle targeted at the driving
assistance is determined as a target from nearby vehicles about
which the communication data processor 10 acquires the vehicle
information. The driving assistance ECU 70 can therefore provide
the driving assistance more accurately reflecting the actual
running condition relation between the most highly prioritized
nearby vehicle targeted at the driving assistance and the subject
vehicle. Moreover, the configuration of the first embodiment
successively determines the most highly prioritized nearby vehicle
targeted at the driving assistance. The targeted nearby vehicle can
therefore be changed accordingly when a variation in the running
situation changes the most highly prioritized nearby vehicle
targeted at the driving assistance.
[0063] The assistance information generated in the assistance
information generator 174 is favorably used for the driving
assistance that assists in driving for a driver by controlling the
subject vehicle travel. This is because a difference between the
generation time of the vehicle information about the subject
vehicle and generation time of the vehicle information about the
nearby vehicle more greatly affects the driving assistance in
driving for a driver by controlling the subject vehicle travel than
the driving assistance providing an alarm.
[0064] (First Modification)
[0065] According to the first embodiment, the target determiner 172
determines, as a prioritized target, the nearby vehicle indicating
the shortest TTC in relation to the subject vehicle, but is not
limited thereto. For example, a distance between the subject
vehicle and each of nearby vehicles may be calculated based on
vehicle positions contained in the vehicle information. The nearby
vehicle indicating the shortest distance calculated may be
determined as a prioritized target. Moreover, a prioritized target
may be determined according to types of the driving assistance
performed in addition to the TTC or the distance between
vehicles.
[0066] Suppose a weighting example that increases the weight
corresponding to a decrease in the TTC or the distance between
vehicles and applies a larger weight to the collision avoidance
assistance than the right turn assistance. In this case, a nearby
vehicle to be prioritized may be more weighted corresponding to the
type of the driving assistance performed. For example, a straight
oncoming vehicle is more weighted than a leading vehicle in
relation to the subject vehicle when the subject vehicle performs
the right turn assistance. A leading vehicle is more weighted than
a straight oncoming vehicle in relation to the subject vehicle when
the subject vehicle performs the collision avoidance assistance.
The weight for the TTC or the distance between vehicles is
integrated with the weight for the type of driving assistance to be
performed. The nearby vehicle indicating the largest integrated
weight can be determined as a prioritized target. It is possible to
preferentially determine the nearby vehicle as a prioritized target
for the driving assistance depending on the type of driving
assistance performed.
Second Embodiment
[0067] The first embodiment provides the configuration that changes
the generation cycle for the vehicle information about the subject
vehicle and thereby suppresses a difference between the time to
generate the vehicle information about the subject vehicle and the
time to generate the vehicle information about the nearby vehicle
used to generate the assistance information. However, the
configuration is not limited thereto. For example, a second
embodiment provides a configuration that changes the generation
cycle for the vehicle information about the nearby vehicle and
thereby suppresses a difference between the time to generate the
vehicle information about the subject vehicle and the time to
generate the vehicle information about the nearby vehicle used to
generate the assistance information.
[0068] The description below explains the second embodiment of the
present invention with reference to the accompanying drawings. The
driving assistance system 3 according to the second embodiment
equals the driving assistance system 3 according to the first
embodiment except that the vehicle-side unit 1 includes a
communication data processor 10a instead of the communication data
processor 10.
[0069] <Schematic Configuration of Communication Data Processor
10a>
[0070] The communication data processor 10a will be described with
reference to FIG. 5. As illustrated in FIG. 5, the communication
data processor 10a includes function blocks such as a sensor
information acquirer 101a, a temporary storage 102a, a data
generator 103, a narrowband communication processor 104, a wide
area communication processor 105, a manager 106, a data processor
107a, and a cycle changer 108a. The communication data processor
10a is also comparable to the vehicle communication control
device.
[0071] The sensor information acquirer 101a equals the sensor
information acquirer 101 according to the first embodiment except
acquiring map data output from the locator 20 around the subject
vehicle in addition to the above-mentioned sensor information. The
temporary storage 102a stores the map data around the subject
vehicle acquired by the sensor information acquirer 101a for a
predetermined time period. The temporary storage 102a equals the
temporary storage 102 according to the first embodiment except
storing map data around the subject vehicle acquired by the sensor
information acquirer 101a.
[0072] As illustrated in FIG. 5, the data processor 107a includes a
data acquirer 171, a target determiner 172, a difference calculator
173, an assistance information generator 174, a map acquirer 175, a
priority determiner 176, and a change requester 177. The data
processor 107a equals the data processor 107 according to the first
embodiment except including the map acquirer 175, the priority
determiner 176, and the change requester 177. The description below
explains the map acquirer 175, the priority determiner 176, and the
change requester 177 included in the data processor 107a.
[0073] The map acquirer 175 acquires the most recent map data
around the subject vehicle stored in the temporary storage 102. The
priority determiner 176 determines which vehicle, the nearby
vehicle or the subject vehicle, should be prioritized, by using the
most recent vehicle position of the nearby vehicle contained in the
data packet acquired by the data acquirer 171, the most recent
vehicle position contained in the vehicle information about the
subject vehicle generated by the data generator 103, and the map
data acquired by the map acquirer 175. The priority determiner 176
can determine which vehicle, the nearby vehicle determined as a
target by the target determiner 172 or the subject vehicle, should
be prioritized, for example.
[0074] Which vehicle, the nearby vehicle or the subject vehicle, is
prioritized can be determined based on which vehicle, the subject
vehicle or the nearby vehicle, is located on a priority road, for
example. Distinction between a priority road and a non-priority
road may be made on condition that the priority road includes a
large number of lanes and the non-priority road includes a small
number of lanes. Alternatively, it may be possible to determine
that the priority road is wide and the non-priority road is narrow.
A combination of these may be used for the determination. For
example, the priority road or the non-priority road may be
determined based on the number of lanes and based on the road
widths when there is no difference between the numbers of lanes.
The other map data elements such as road types may be used to
determine the priority road or the non-priority road.
[0075] Suppose the priority determiner 176 determines that the
nearby vehicle is prioritized. In this case, similarly to the first
embodiment, a change is made to the generation cycle for the data
generator 103 to generate the vehicle information about the subject
vehicle so as to decrease a difference calculated by the difference
calculator 173. Suppose the priority determiner 176 determines that
the subject vehicle is prioritized. In this case, the change
requester 177 issues a request to the vehicle-side unit 1 of the
nearby vehicle so as to change the generation cycle of the vehicle
information. The change requester 177 will be described below.
[0076] When the priority determiner 176 determines that the subject
vehicle is prioritized, the change requester 177 issues request
information to the vehicle-side unit 1 of the nearby vehicle
determined as a target by the target determiner 172. The request
information requests a change in the generation cycle of the
vehicle information. For example, the request information contains
a difference calculated by the difference calculator 173 between
the subject vehicle and the targeted nearby vehicle. The
description below according to the embodiment uses an example where
the request information contains a difference calculated in the
difference calculator 173 by subtracting the generation time to
generate the most recent vehicle information about the targeted
nearby vehicle from the generation time to generate the most recent
vehicle information about the subject vehicle.
[0077] The change requester 177 transmits the request information
to the wide area communication processor 105, for example. The
request information is thereby transmitted to the targeted nearby
vehicle via the wide area communication processor 105, the DCM 40,
and the center 2. In this case, the wide area communication
processor 105 generates a data packet containing the request
information. The data packet containing the request information is
transmitted to the targeted nearby vehicle from the DCM 40 via the
center 2 similarly to the data packet containing the vehicle
information as described in the first embodiment. It is favorable
to use a communication method capable of transmitting the request
information by specifying a transmission destination. The request
information may be transmitted along with the vehicle information
when transmitted.
[0078] The data packet containing the request information, after
transmitted, is received at the DCM 40 of the vehicle-side unit 1
mounted on the nearby vehicle and is transmitted to the wide area
communication processor 105 of the communication data processor 10a
on the nearby vehicle. The data packet is transmitted to the cycle
changer 108a from the wide area communication processor 105 via the
manager 106 and the data processor 107a.
[0079] The cycle changer 108a is similar to the cycle changer 108
according to the first embodiment except that the cycle changer
108a changes the generation cycle for the vehicle information about
the subject vehicle based on the request information contained in
the data packet transmitted from the data processor 107a. The cycle
changer 108a changes the generation cycle for the data generator
103 to generate the vehicle information about the subject vehicle
so as to decrease the difference contained in the request
information. In the example according to the present embodiment,
the difference contained in the request information is found by
subtracting the generation time to generate the vehicle information
about the subject vehicle from the generation time to generate the
vehicle information about another vehicle as an origin to transmit
the request information. When the difference contained in the
request information represents a positive value, the generation
cycle for the vehicle information about the subject vehicle needs
to be increased to meet the time corresponding to the difference.
When the difference contained in the request information represents
a negative value, the generation cycle for the vehicle information
about the subject vehicle needs to be decreased to meet the time
corresponding to the difference.
[0080] A flowchart in FIG. 6 is used to illustrate a flow of the
generation cycle changing and related process concerning a change
in the generation cycle for the vehicle information in the
communication data processor 10a. The flowchart in FIG. 6 may start
when an ignition power supply of the subject vehicle turns on, for
example. However, the following assumes that the flowchart starts
when the subject vehicle enters the vicinity of a predetermined
position. The vicinity of the predetermined position can signify an
area within a predetermined distance from the center of an
intersection with no traffic light or an area within a
predetermined distance from a high-accident location. The data
processor 107a may determine entry into the vicinity of the
predetermined position based on the vehicle position of the subject
vehicle and map data, for example.
[0081] Step S21 is similar to S1 as above. The process proceeds to
step S22 when a processing cycle is available (YES at S21). The
process proceeds to step S28 when a processing cycle is unavailable
(NO at S21). The process at step S22 and step S23 equals that at S2
and S3 as above.
[0082] At step S24, the priority determiner 176 determines which
vehicle, the nearby vehicle determined as a target at S24 or the
subject vehicle, is prioritized. At step S25, when the priority
determiner 176 determines that the subject vehicle is prioritized
(YES at S25), the process proceeds to S26. When the priority
determiner 176 determines that the nearby vehicle is prioritized
(NO at S25), the process proceeds to step S27.
[0083] At step S26, the change requester 177 transmits request
information to the vehicle-side unit 1 of the nearby vehicle
determined as a target at S24. The request information requests a
change in the generation cycle of the vehicle information. The
process then proceeds to step S28. The process at step S27 equals
that at S4 above.
[0084] At step S28, when the generation cycle changing and related
process reaches the termination timing (YES at S28), the generation
cycle changing and related process terminates. When the generation
cycle changing and related process does not reach the termination
timing (NO at S28), the process returns to S21 and is repeated. The
generation cycle changing and related process may reach the
termination timing when the subject vehicle exits from the vicinity
of a predetermined position or when the ignition power supply of
the subject vehicle turns off, for example. The data processor 107a
may determine exit from the vicinity of the predetermined position
based on the vehicle position of the subject vehicle and map data,
for example.
[0085] The second embodiment shortens the generation cycle for the
vehicle information about the targeted nearby vehicle by the time
corresponding to a difference found by subtracting the generation
time to generate the most recent vehicle information about the
nearby vehicle from the generation time to generate the most recent
vehicle information about the subject vehicle. It is therefore
possible to eliminate a difference between the generation time for
the vehicle information acquired next from the nearby vehicle via
the communication and the generation time for the vehicle
information generated next in the subject vehicle. The second
embodiment can therefore also minimize dissatisfaction of a driver
with the driving assistance using vehicle information about the
nearby vehicle acquired by communication from outside the subject
vehicle and vehicle information about the subject vehicle acquired
in the subject vehicle. The second embodiment can suppress a
difference in the vehicle information generation time between a
vehicle traveling the priority road and a vehicle traveling the
non-priority road without changing the generation cycle for the
vehicle information about the vehicle traveling the priority
road.
[0086] (Second Modification)
[0087] As has been described, the second embodiment determines
which vehicle, the nearby vehicle or the subject vehicle, should be
prioritized, based on which vehicle, the nearby vehicle or the
subject vehicle, is located on the priority road. However, the
embodiment is not limited thereto. It may be possible to prioritize
the subject vehicle or the nearby vehicle based on other factors
such as a distance from a predetermined position, namely, to
prioritize the subject vehicle or the nearby vehicle whichever
indicates its vehicle position nearer to a predetermined position.
The predetermined position signifies any configurable spot such as
the center of an intersection with no traffic light or a
high-accident location.
[0088] (Third Modification)
[0089] According to the above-mentioned embodiments, plural types
of communication paths transmit the common vehicle information to
the communication data processor 10, but not limited thereto. Only
one type of communication path may be used, for example.
[0090] (Fourth Modification)
[0091] The above-mentioned embodiment provides the communication
data processor 10 or 10a separately from communication modules such
as the inter-vehicle communication instrument 30 and the DCM 40,
but is not limited thereto. For example, the communication data
processor 10 or 10a may be integrated with the above-mentioned
communication modules.
[0092] (Fifth Modification)
[0093] The above-mentioned embodiment provides the communication
data processor 10 or 10a separately from the driving assistance ECU
70, but is not limited thereto. For example, the communication data
processor 10 or 10a may be integrated with the driving assistance
ECU 70.
[0094] Although the present disclosure is described based on the
above embodiments, the present disclosure is not limited to the
embodiments and the structures. Various changes and modification
may be made in the present disclosure. Furthermore, various
combination and formation, and other combination and formation
including one, more than one or less than one element may be made
in the present disclosure.
* * * * *